Today, Microsoft announced a new feature for its game-streaming service Mixer, called Direct Purchase. With the feature, users will be able to purchase games or DLC that the streamer is using, without ever leaving the Mixer interface.
To make it even sweeter, the streamer will get a 5% kickback when you make your purchase, so not only will you be buying the game you're seeing, but you're also supporting your favorite players. The streamers will be able to choose the content that they promote; they can pick a version of a game (base, deluxe, ultimate, etc.), or individual content like DLC.
The content that users can purchase will be anything from the Microsoft Store, including games for Xbox, Windows 10, and Xbox Play Anywhere. Obviously, that means that players can't add purchases for games from third-party vendors like Steam.
Microsoft acquired Mixer in August 2016, back when it was called Beam. The company wasted no time integrating the service into Windows 10, Xbox One, and Microsoft services. Starting with the Creators Update last spring, players were able to broadcast their games from right within the OS. Mixer has been working hard on new features ever since.